PHOENIX (AP) — Robert Redford will join conservationists from across the U.S. and Mexico at an event Saturday in Phoenix aimed at raising money and awareness for the restoration of part of the overtaxed Colorado River that has become more desert than delta.

The actor is slated to speak at a gala at the Arizona Science Center as a coalition of environmental groups launches a fundraising drive for the project. He also plans to screen “Watershed,” a documentary on the river system produced by him and his son, Jamie Redford.

Colorado River Campaign director Gary Wockner also will attend. He said if nothing is done to restore the river, it will continue to be “bone-dry and never reach the sea again.”

“This is a huge opportunity in river restoration, where the two countries have agreed to do something about this,” Wockner said.

Wockner said the Colorado River used to have 2 million acres of wetlands in the delta, which lies in the Gulf of California in Mexico. Organizers are aiming to raise $10 million by 2017. So far, $2 million has been raised. The money would go toward restoration and acquiring water rights from farmers in Mexico, Wockner said.

Francisco Zamora is director for the Colorado River Delta program at the Tucson-based Sonoran Institute, one of the groups behind the fundraiser. He said a little bit of restored water can go a long way in bringing back critical habitats.

“There is hope, we know, because we have been working for more than 10 years, and we have seven to eight years of doing on-the-ground restoration,” Zamora said. “We know we can bring back some of those habitats.”

Looming shortages are predicted on the river serving some 40 million people in California, Arizona, Colorado, Nevada, Utah, New Mexico and Wyoming. Mexico also has a stake.

Earlier this year, federal officials declared that the river already described as the most plumbed and regulated in the world would be unable to meet demands of a growing regional population over the next 50 years.

Jamie Redford says municipalities, agriculturists and consumers can be part of the solution by cutting down their water waste.

“There’s so much economic activity, so much going on on that river,” he said. “If you take it apart bit by bit, if you get a critical mass going, doing little bit by little bit will all add up. There is so much room for improvement.”